Method and apparatus for making brush segments



Nov. 14, 1967 s. .1. MELCHER 3,352,604

METHOD AND APPARATUS FOR MAKING BRUSH SEGMENTS Original Filed Dec. 28,1961 2 Sheets-Sheet 1 INVENTOR. 6L 5 J Ma CHER Nov. 14, 1967 G. J.MELCHER 3,352,604

METHOD AND APPARATUS FOR MAKING BRUSH SEGMENTS Original Filed Dec. 28,1961 2 Sheets-Sheet 2 g INVENTOR 6L 5 J Mac/1n? A r TORNEYS UnitedStates Patent 3,352,604 METHOD AND APPARATUS FOR MAKING BRUSH SEGMENTSGlee J. Melclrer, Spokane, Wash, assignor to Owens- Corning FiberglasCorporation, a corporation of Delaware Original application Dec. 28,1961, Ser. No. 162,842, now Patent No. 3,233,270, dated Feb. 8, 1966.Divided and this application Oct. 24, 1965, Ser. No. 513,894

8 Claims. (Cl. 300--1) This application is a division of my copendingapplication Ser. No. 162,842, filed in the name of the present inventoron Dec. 28, 1961, and now patent No. 3,233,270, issued Feb. 8, 1966.

This invention relates to brooms and apparatus for making them.

More specifically the invention pertains to the fabrication of broomsegments particularly adapted for assembling into a cylindrical broom orbrush for street sweepmg.

The invention further relates to broom bristles having a fibrous glassbase and a heavy outer layer of plastic.

The majority of the machines for street cleaning utilize a largecylindrical broom revolving about a horizontal axis. These machines aregenerally pick-up sweepers in which the broom projects the debris upon aconveyor which carries it to a hopper.

Still in limited use is an older type of machine utilizing a similarcylindrical broom mounted at an angle to the direction of travel forsweeping the dirt into a windrow at the side of the pavement forsubsequent collection.

Split hickory, bass, palmyra, split bamboo, steel and more recentlysynthetic fibers of nylon, polystyrene and polypropylene have been usedfor the bristles in these brooms.

The median life of these cylindrical brooms with vegetable fiberbristles has been between 200 or 300 curb miles, a distance easilycovered within one week. Accordingly, the cost of a new broom and thelabor cost of removal and replacement is incurred at frequent intervals.The loss of the use of the machine for the replacement operationrequires additional equipment or delays the cleaning of streets.

Steel bristles are expensive, subject to corrosion, and areobjectionable because of the broken metal pieces which are shredded andleft behind. For air strip cleaning these metal remnants areparticularly dangerous as they are apt to be drawn into the air take ofjet aircraft.

The cost of the synthetic bristles is even higher than that of steel.Further, these bristles are of materials which are inclined to absorbwater and are objectionable in this respect. They further do notgenerally have the desired flexibility.

-An object of this invention is the provision of bristles of reasonablecost and which have a long life with uniform flexibility mostadvantageous for street sweeping.

More specifically, an object is to provide a method of making bristlesof fibrous glass and a plastic overlay.

A further object is a method of coating fibrous glass strands with afluid plastic, positioning the strands in bristle formation in a brushsegment, and then setting the plastic coating of the strands.

Also an object of this invention is the provision of apparatus forcoating fibrous glass strands while wrapping them traversely upon arotating reel,

A further object is the provision of shaped brush segments in which thebristles are in fixed relation and in definite rows and a method offabricating such brush segments.

An additional object is to provide brush segments facilitating originalassembly and adapted for rapid replacement upon a brush core.

3,352,604 Patented Nov. 14, 1967 These as well as other objects andadvantages are attained at least in part by coating fibrous glassrovings with a hardenable plastic resin just prior to winding therovings upon a brush segment forming reel and setting the resin afterthe rovings have been so arranged.

The invention will be explained more completely hereafter in connectionwith the drawings in which:

FIGURE 1 is a perspective view of apparatus designed for creating brushsegments according to the invention;

FIGURE 2 is an enlarged sectional view of a completed double brushsegment on the apparatus of FIGURE 1;

FIGURE 3 is a sectional view of two brush segments formed from thedouble segment illustrated in FIGURE 2 after it has been sheared alongits mid-section and removed from the apparatus;

FIGURE 4 is a sectional View on an enlarged scale of a clampingarrangement for holding brush backing strips on longitudinal members ofthe reel of the apparatus of FIGURE 1;

FIGURE 5 is a perspective view of a core adapted to receive the brushsegments of this invention; and

FIGURE 6 is an end View of the core of FIGURE 5 with the brush segmentsmounted thereon.

Referring to the drawings in more detail the apparatus of FIGURE 1includes a base formed of end blocks 10 and 11. Two uprights 16 and 17of the frame blocks provide bearing apertures for the center shaft 21 ofa ro tatable reel assembly 22.

The reel has a pair of longitudinal members 24 and 25 slightly more thansixty inches in length and spaced twenty-four inches apart. These arecylindrical in form and are secured at their ends to cross pieces 27 and28. Cross pieces 27 and 28 are fixed to shaft 21. On the outer end ofshaft 21 projecting through upright 17 is a pulley 34 driven by motor 36through motor pulley 37 and belt 39. Through this drive the reelassembly 22 is rotated at the desired speed.

On the near side of the apparatus, as seen in FIGURE 1, is adouble-threaded lead screw or cylindrical cam 41 rotatably journaled inbearings 42 and 43 supported on the frame blocks 10 and 11. The leadscrew 41 is turned by a belt 45 running between pulley 46 on the end ofthe lead screw and pulley 48 on the shaft 21 projecting through block11.

A carriage 50 has a pivotable lug (not shown) riding in the threading ofthe lead screw 41 and the carriage is moved lengthwise of the reel 22 bythe continuous engagement of the lug with the lead screw. The carriage50 is further supported by a lateral leg 52 which slides upon the rail54 extending between frame members 10 and 11. Mounted on the carriage 50is a resin container 56.

Rovings 58, in this example five in number, are delivered from spools 63and directed under a coating roller 60 within the resin container afterpassing through spaced guide eyes 61. Exit guiding apertures 62 for therovings remove excess resin therefrom.

Other structural features of the apparatus will be described in thesubsequent explanation of the operation of the apparatus.

A preferred roving for the practice of the invention is one about .06 ofan inch in diameter and made up of sixty ends of strand composed ofcontinuous glass filaments with an average filament diameter -of-.00036of an inch and each strand having 13,500 feet of length, per pound.

To provide compatability and good bonding characteristics between theroving and the resin, preferably utilized to coat the roving, the latteris finished with a chrome size. A well known type is a methacrylatechromic chloride complex, neutralized with ammonia.

As disclosed, five of the rovings 58 are drawn from spools 63. They areled through guide eyes 61 and under the resin applicator roller 60within the container 56 3 which initially is at the left end of the leadscrew 41, as viewed in FIGURE 1. After being passed through the wipingguides 62 they are fastened to the end of one of the longitudinalmembers 24 or 25 of the reel 22 and are spaced apart about three-tenthsof an inch.

Held at each end of the longitudinal members by a U-bolt 64, strap 65and nuts 66, as best seen in FIGURE 4, are pairs of brush back formingstrips 67 and 68 of arcuate cross section. These extend along oppositesides of the outer portion of each member 24 and 25.

The preferred resin is a general purpose polyester (cont-ainingmonomeric styrene, diallyl phthalate, or vinyltoluene as cross-linkingagents) catalyzed for fast curing at room temperature. Such a resin isavailable at low cost and has the stiffness, strength, and resiliencedesired in a bristle for street sweeping.

The resin should be sufficiently viscous for each roving to pick up aresin coating of a weight approximately equal to that of the roving. Inthis case, this is a coating about .02 of an inch thick which increasesthe diameter of the roving to approximately one-tenth of an inch.

The reel 22 maybe turned, for instance, at thirty revolutions a minutewith the carriage driven at a speed whereby it makes a single traversefor every forty revolutions of the reel. This would space each turn ofcoated rovings about three-tenths of an inch apart, the same spacingexisting between the five individual rovings of each set, as they arewrapped upon the reel.

After the full traverse of the carriage 50, with the coated rovingswrapped around a five foot span of the reel, a rod or sticker aboutone-quarter of an inch-in diameter is placed against each side of thewrapped form or shell of rovings alongside of the shaft 21 midwaybetween the longitudinal members 24 and 25. An original pair of suchrods 70 and 71 may be so mounted before the wrapping of the rovings isinitiated.

These rods are positioned through openings in spacers 72 and 74 fixed tothe cross pieces 27 and 28 and through openings in a spacer 73 fastenedto the shaft 21 at its center point. After a second pair of rods 77 areplaced along the outside of the first Wrapping of the rovings, reel 22is again rotated and the cam'age "50 with the resin container is movedin the opposite direction through the action of the lug on the carriagefollowing the opposite threading of the lead screw 41.

The second skein or layer of rovings formed by the second traverse ofthe carriage 50 is held about a quarter of an inch out from the firstlayer at the midpoint between the longitudinal members 24 and 25 by thepair of rods or stickers 77. This spacing establishes the final rowspacing arrangement of bristles in the brush.

After the second traverse of the resin carriage another pair of rods 79are positioned through the spacers in the holes adjacent to thosethrough which the pair 77 were inserted. This positions the next layerof rovings onequarter of an inch out from the preceding layer.

For a total of thirteen traverses this procedure is repeated withadditional pairs of rods 79 inserted after each traverse. In theresulting composite shell of coated rovings wrapped on the reel therovings are closely contiguous or in contact with each other as theypass over the longitudinal members 24 and 25 but form thirteen stratadiverging slightly from these members to a maximum spacing betweenstrata of one-quarter of an inch midway between the members.

While the resin is still sticky two narrow reinforcing wooden slats 81and 82 are attached at the sides of the narrow ends of the shell ofrovings outside of the location of the back forming pieces 67 and 68. Across section of the reel with the roving shell forming a double brushsegment thereon is shown in FIGURE 2.

The plastic resin is allowed to harden and then rods 77 and 79 areremoved by drawing them out lengthwise through the apertures of spacers72, 73 and 74. The rods are waxed or carry some other releasing coatingwhich 4 prevents the resin from adhering to them. To form two broomsegments the shell or double segment is cut by shears along both sidesof the line dd, shown in FIG- URE 3, and the two brush segments 85 maythen be removed from the reel and appear as illustrated in FIG- URE 3.

The resulting five foot long brush segments 85 with bristles twelveinches in length have a continuous film of hardened resin between andimbedding the rovings around the base 87 of each segment. This is thickenough to have considerable strength to bond the bristles together andto hold the shape of the segment. The strips 67 and 68 and slats 81 and82 are also held firmly in place by this resin film and cooperate withit in serving as the brush backing or base 87.

A brush or broom core 90 particularly adapted for receipt of twelve ofthe brush segments 85 is illustrated in FIGURE 5. It has hubs 92 boredfor receipt of mounting and driving shafts for rotating the brushassembly. Extending lengthwise of the core and welded to the hubs 92 andto a center reinforcing wheel 93 are twelve outwardly facing channels94. These are dimensioned to receive the bases of the brush segments. Tohold the latter firmly in proper positioning, retaining bars 96 ofsemicylindrical form are fitted against the curved portions of thestrips 67 and 63. These are tightened in place by bolts 98 passedthrough the bars 96, the resin film backing of the brush segments andholes 101 in the channels 94. The

bolts are threaded into nuts 99 Welded to the underside of the channels.

The features of the invention include the traversing of the combinationroving feeder and coater, the positioning of the coated roving rows infinal bristle arrangement and setting the resin thereafter, the creationof a heavy, reinforcing, continuous resin film at the base of eachsegment, polyester coated glass strands of brush bristles and the brushsegment design and assembly upon a brush core.

The glass strand utilized for the bristle base may of course be ofvarious structures and sizes other than the rovings prescribed herein.With a lighter roving, closer spacing of the bristles of each row and ofthe rows themselves would be desirable. The term strand is utilized inthe claims to indicate any fibrous glass roving, yarn, strand or cordthat might serve as a bristle base.

Other resins than polyester would be quite as adequate. These could beeither thermosetting or thermoplastic. In the prescribed quantity andviscosity of resin applied to the strands any of such resins shouldmerge to 'form a continuous, solid film encasing the contiguous glassstrands at the base of each brush segment; The consolidation of lasticresin and lass strands in this area creates in effect,

a plastic backing reinforced with glass strands.

While a reel rotatable on a horizontal axis is considered the mostfeasible arrangement for practicing the invention, the reel could, ofcourse, be mounted for rotation on a vertical axis or one inclined tothe horizontal. The grinding of the rovings for wrapping upon a reeloperating 'so angled would be more troublesome but would not present toodifiicult a problem.

In another possible, but likewise unpreferred alternate method, the reelcould be held stationary and the coated roving guided around it. Theguiding means would --be moved lengthwise of the reel as well as aroundit. In

such an installation, it might be advisable to also have the coatingdevice and the spools of roving follow the movement of the guidingmeans.

Another modification of the invention involves wrapping the coatedstrands around the reel under sufficient tension and with the resincoating soft enough that each strand and its coating is flattened as itpasses over the spacing rods 70, 71, 77 and 79. This flattening extendsalong the strands away from their actual contact with the rods. With thestrands so shaped, the setting of the resin results in bristles ofsomewhat blade form. When incorporated in acylindrical brush assemblythe broadened sides of the bristles face the direction of rotation andpresent a greater area for driving contact with the debris or snow beingcollected.

Also, different spacing members may be utilized to vary the number andspacing of rows of bristles. The speed of production is another factorthat may be altered according to conditions. That given as an exampleherein in describing the apparatus is lower than would be normallyutilized.

Other modifications and substitutions will occur to those skilled in theart without departing from the spirit of the invention and the confinesof the following claims.

I claim:

1. A method of making brush segments comprising wrapping successivelayers of strand material upon a rectangular reel, separating each layerof such successive layers along the center of the reel as strandmaterial is wrapped thereon, heavily coating such strand material with asettable liquid resin as the strand material is wrapped upon the reel,setting the liquid resin while the strand material is wrapped on thereel, and thereafter removing the thus stiffened strand material fromthe reel.

2. A method according to claim 1 in which the liquid resin is apolyester.

3. Apparatus for making brush segments including a generally planar,rectangular reel, means for delivering bristle forming strand materialand Wrapping such material in successive overlying layers around thereel, and rods associated with the reel extending lengthwise between theedges thereof for holding each of such layers apart along the center ofthe generally planar sides of the reel, the rods being removably fixedin spaced relation to the reel and means temporarily holding brushsegment base members on the reel.

4. Apparatus for making brush segments including a generally planar,rectangular reel, means for delivering bristle forming strand materialand wrapping such material in successive overlying layers around thereel, and rods associated with the reel extending lengthwise between theedges thereof for holding each of such layers 6 apart along the centerof the generally planar sides of the reel, the rods being removablyfixed on the reel and spaced a distance greater than the thickness ofthe layers.

5. Apparatus for making blush segments including a generally planar reelhaving parallel lengthwise edges, a plurality of pairs of removablymounted rods extending lengthwise on the reel between its length-wiseedges, the individual rods of each pair of rods being located onopposite sides of the plane of the reel an equal distance from theplane, each succesive pair of rods being laterally spaced apart from afirst pair of rods proximate to the plane to more remote pairs; andmeans for wrapping bristle forming material in layers around the reeland rods, one layer of the material being wrapped on each pair of rods,each layer of material contacting its immediately underlying layer alongthe lengthwise edges of the reel, each layer diverging from the edges toa separation between individual layers at the rods equal to the spacingbetween the rods.

6. Apparatus for making brush segments as recited in claim 5 where thepairs of rods are disposed substantially midway between the lengthwiseedges of the reel.

7. Apparatus for maikng brush segments as recited in claim 6 where therods are mounted for removal along the length of the reel.

8. Apparatus for making brush segments as recited in claim 7 where thereel is a generally rectangular planar reel.

References Cited UNITED STATES PATENTS GRANVILLE Y. CUSTER, IR., PrimaryExaminer.

3. APPARATUS FOR MAKING BRUSH SEGMENTS INCLUDING A GENERALLY PLANAR, RECTANGULAR REEL, MEANS FOR DELIVERING BRISTLE FORMING STRAND MATERIAL AND WRAPPING SUCH MATERIAL IN SUCCESSIVE OVERLYING LAYERS AROUND THE REEL, AND RODS ASSOCIATED WITH THE REEL EXTENDING LENGTHWISE BETWEEN THE EDGE THEREOF FOR HOLDING EACH OF SUCH LAYERS APART ALONG THE CENTER OF THE GENERALLY PLANAR SIDES OF THE REEL, THE RODS BEING REMOVABLY FIXED IN SPACED RELATION TO BASE MEMBERS ON THE REEL. 